Rights management and enforcement is highly desirable in connection with digital content such as digital audio, digital video, digital text, digital data, digital multimedia, etc., where such digital content is to be distributed to one or more users. Digital content could be static, such as a text document, for example, or it could be streamed, such as the streamed audio/video of a live event. Typical modes of distribution include tangible devices such as a magnetic (floppy) disk, a magnetic tape, an optical (compact) disk (CD), etc., and intangible media such as an electronic bulletin board, an electronic network, the Internet, etc. Upon being received by the user, such user renders the digital content with the aid of appropriate rendering software such as an audio player, a text displayer, etc. on a personal computer or other hardware.
In one scenario, a content owner or rights-owner such as an author, a publisher, a broadcaster, etc., wishes to distribute such digital content to each of many users or recipients in exchange for a license fee or some other consideration. In such scenario, then, the content may be an audio recording, a multimedia presentation, etc., and the purpose of the distribution is to generate the license fee. Such content owner, given the choice, would likely wish to restrict what the user can do with such distributed digital content. For example, the content owner would like to restrict the user from copying and re-distributing such content to a second user, at least in a manner that denies the content owner a license fee from such second user.
In addition, the content owner may wish to provide the user with the flexibility to purchase different types of use licenses at different license fees, while at the same time holding the user to the terms of whatever type of license is in fact purchased. For example, the content owner may wish to allow distributed digital content to be rendered only a limited number of times, only for a certain total time, only on a certain type of machine, only on a certain type of rendering platform, only by a certain type of user, etc.
In another scenario, a content developer, such as an employee in or member of an organization, wishes to distribute such digital content to one or more other employees or members in the organization or to other individuals outside the organization, but would like to keep others from rendering the content. Here, the distribution of the content is more akin to organization-based content sharing in a confidential or restricted manner, as opposed to broad-based distribution in exchange for a license fee or some other consideration.
In such scenario, then, the content may be a document presentation, spreadsheet, database, email, or the like, such as may be exchanged within an office setting, and the content developer may wish to ensure that the content stays within the organization or office setting and is not rendered by non-authorized individuals, such as for example competitors or adversaries. Again, such content developer wishes to restrict what a recipient can do with such distributed digital content. For example, the content owner would like to restrict the user from copying and re-distributing such content to a second user, at least in a manner that exposes the content outside the bounds of individuals who should be allowed to render the content.
In addition, the content developer may wish to provide various recipients with different levels of rendering rights. For example, the content developer may wish to allow protected digital content to be viewable and not printable with respect to one class of individual, and viewable and printable with respect to another class of individual.
However, and in either scenario, after distribution has occurred, such content owner/developer has very little if any control over the digital content. This is especially problematic in view of the fact that practically every personal computer includes the software and hardware necessary to make an exact digital copy of such digital content, and to download such exact digital copy to a write-able magnetic or optical disk, or to send such exact digital copy over a network such as the Internet to any destination.
Of course, as part of a transaction wherein the content is distributed, the content owner/developer may require the user/recipient of the digital content to promise not to re-distribute such digital content in an unwelcome manner. However, such a promise is easily made and easily broken. A content owner/developer may attempt to prevent such re-distribution through any of several known security devices, usually involving encryption and decryption. However, there is likely very little that prevents a mildly determined user from decrypting encrypted digital content, saving such digital content in an un-encrypted form, and then re-distributing same.
RM and enforcement architectures and methods have thus been provided to allow the controlled rendering of arbitrary forms of digital content, where such control is flexible and definable by the content owner/developer of such digital content. Such architectures allow and facilitate such controlled rendering in either scenario as set forth above.
Typically, a digital license is tied to a global or near-global root trust authority, for example by way of a chain of digital certificates, and thus any entity that wishes to authenticate/verify such license must be in possession of appropriate information relating to such root trust authority. However, and as should be appreciated, situations can occur where an entity through no fault of its own is not in fact in possession of such appropriate information and therefore cannot so authenticate/verify the license. For one example, the information may have changed since the entity received a copy. For another example, the root trust authority may have changed.
In either example, it should be evident that having the entity rely on any particular root trust authority without regard for any other root trust authority is fraught with danger. In essence, the entity always relies on the particular root trust authority and the information thereof, even when other root trust authorities exist are come into existence, and even if the particular root trust authority goes out of existence.
Accordingly, a need exists for a more flexible architecture for defining digital licenses and the operation thereof. In particular, a need exists for such an architecture that allows for multiple root trust authorities and that allows a license to itself specify each root trust authority that can be employed to authenticate/verify same. Moreover, to effectuate such architecture, a need exists for a new type of license that comprises a plurality of license documents.